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 Question by Patrick Meadows posted 05 Feb 2001
I am a little confused on the T568A & T568B wiring schemes. I lloked at all my patch CAT5 cords and/or and RJ45 jacks I recently purchased to install a Dlink DI-704 DSL gateway product. All the cables are marked as 568A, but the pin outs match your diagram as 568B ?? I also have some patch cables marked as 568A with the GRN-R BLK-YEL OR-BLU BRN-W colour code. They have the same pin assignment linup as your diagram 568B. I'm confused. Thanks for your help
 Answer by Roman Kitaev posted 05 Feb 2001
Hi, Patrick!

Yes, you are right, this may cause confusion.

There is a cabling standard titled TIA/EIA 568-A. It defines *transmission parameters* for cables and components and gives definitions for Category 3 and Category 5. When a cable or component is marked as "568A", it means that it complies to some transmission Category from this standard.

This standard also defines two wiring pinout schemes confusingly titled T568A and T568B. The pinout assignment just tells us, which cable pair connects to which pin at the outlet or connector.

In summary, in your case nothing is wrong. You have a cable or cord compliant with TIA/EIA-568-A standard (i think it's Category 5) and cords and outlets wired using T568B wiring scheme.

Hope it helps
Roman Kitaev, RCDD

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